A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
A light gray wall or floor (you decide) of concrete.
Source Atle Mo
A seamless pattern of dark bricks. Maybe it's not very realistic, but it looks good in my opinion.
Source V. Hartikainen
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
A free background pattern with abstract green tiles.
Source V. Hartikainen
Classic 45-degree pattern, light version.
Source Luke McDonald
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
An abstract Background pattern of purple twisty patterns.
Source TikiGiki
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
Light gray paper pattern with small traces of fiber and some dust.
Source Atle Mo
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Prismatic Rounded Squares Grid 3 No Background
Source GDJ
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo
8 by 8 pixels, and just what the title says.
Source pixilated
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Just a nice looking textured pattern with faded blue stripes. Well, that's it for today... one background a day, as usual.
Source V. Hartikainen
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin